Re: [Flexradio] Sound card input Voltage
Cecil, Anybody know where I can find a sound card with 180 dB dynamic range for less than $200? Sorry, Thats the $4000 (or much more) question.. And 60MHz clock..would be fine groeten Peter petervn(a)hetnet.nl mailto:[EMAIL PROTECTED] ; pa0pvn(a)hetnet.nl mailto:[EMAIL PROTECTED] ; pa0pvn(a)gmail.com ; pa0pvn(a)amsat.org . Van: [EMAIL PROTECTED] namens k5nwa Verzonden: zo 15-4-2007 19:56 Aan: Sami Aintila CC: flexradio@flex-radio.biz Onderwerp: Re: [Flexradio] Sound card input Voltage Thanks everyone for the answers, I suspected I had it wrong and I did. I have an output in dBm at 50 Ohms, using a transformer to convert the impedance from 50 ohms to 600 Ohms then output in DBU would be the voltage at 50 Ohms times the square root of the impedance ratio or 3.46 times higher than the 50 Ohm ? +14 dBm = 1.1V at 50 Ohms convert to 600 ohms with a transformer and you have 3.8V at 600 Ohms or 10.7V PP +26dBm gain prior to that and I end up with -12 dBm input or higher will start getting you in trouble. Anybody know where I can find a sound card with 180 dB dynamic range for less than $200? At 03:40 AM 4/15/2007, Sami Aintila wrote: Usually for audio applications dBm should be referenced to one milliwatt into a 600-ohm load. (Your dBm figure is using 50 ohms). In order to avoid confusion when we're measuring voltages, it's better to not use dBm at all. For voltages, it's probably easiest to use dBV referenced to one volt RMS. (There's also dBu which is equivalent to dBm @ 600 ohms.) To answer your original question, while the Delta 44 may not be a typical sound card, its input range (peak-to-peak) seems to be 11 Vpp. That's about 5.5 Vpeak, 3.9 Vrms, +12 dBV (+14 dBu). The maximum input level is 6 dB lower when using the consumer setting in D44's control panel. And using the lowest setting means another -6 dB. That would be 0 dBV == 1 Vrms. Maybe that's pretty close to a typical (cheap) sound card. 73, Sami OH2BFO On 4/15/07, k5nwa [EMAIL PROTECTED] wrote: What is the full scale input to a typical sound card? I'm thinking it's +10dBm or .7V, am I off my rocker? Cecil K5NWA www.qrpradio.com www.hpsdr.com Blessed are the cracked, for they shall let in the light. Cecil K5NWA www.qrpradio.com www.hpsdr.com Cum catapultae proscriptae erunt tum soli proscripti catapultas habebunt. (When catapults are outlawed, only outlaws will have catapults!) ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/ -- next part -- An HTML attachment was scrubbed... URL: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/attachments/20070416/8c749294/attachment.html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Usually for audio applications dBm should be referenced to one milliwatt into a 600-ohm load. (Your dBm figure is using 50 ohms). In order to avoid confusion when we're measuring voltages, it's better to not use dBm at all. For voltages, it's probably easiest to use dBV referenced to one volt RMS. (There's also dBu which is equivalent to dBm @ 600 ohms.) To answer your original question, while the Delta 44 may not be a typical sound card, its input range (peak-to-peak) seems to be 11 Vpp. That's about 5.5 Vpeak, 3.9 Vrms, +12 dBV (+14 dBu). The maximum input level is 6 dB lower when using the consumer setting in D44's control panel. And using the lowest setting means another -6 dB. That would be 0 dBV == 1 Vrms. Maybe that's pretty close to a typical (cheap) sound card. 73, Sami OH2BFO On 4/15/07, k5nwa [EMAIL PROTECTED] wrote: What is the full scale input to a typical sound card? I'm thinking it's +10dBm or .7V, am I off my rocker? Cecil K5NWA www.qrpradio.com www.hpsdr.com Blessed are the cracked, for they shall let in the light. ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Cecil, A convenient on-line calculator for signal level conversions is this: http://www.analog.com/Analog_Root/static/techSupport/designTools/interactiveTools/dbconvert/dbconvert.html 73, Ahti OH2RZ On 15/04/07, Sami Aintila [EMAIL PROTECTED] wrote: Usually for audio applications dBm should be referenced to one milliwatt into a 600-ohm load. (Your dBm figure is using 50 ohms). In order to avoid confusion when we're measuring voltages, it's better to not use dBm at all. For voltages, it's probably easiest to use dBV referenced to one volt RMS. (There's also dBu which is equivalent to dBm @ 600 ohms.) To answer your original question, while the Delta 44 may not be a typical sound card, its input range (peak-to-peak) seems to be 11 Vpp. That's about 5.5 Vpeak, 3.9 Vrms, +12 dBV (+14 dBu). The maximum input level is 6 dB lower when using the consumer setting in D44's control panel. And using the lowest setting means another -6 dB. That would be 0 dBV == 1 Vrms. Maybe that's pretty close to a typical (cheap) sound card. 73, Sami OH2BFO On 4/15/07, k5nwa [EMAIL PROTECTED] wrote: What is the full scale input to a typical sound card? I'm thinking it's +10dBm or .7V, am I off my rocker? Cecil K5NWA www.qrpradio.com www.hpsdr.com Blessed are the cracked, for they shall let in the light. ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Original Message Cecil, A convenient on-line calculator for signal level conversions is this: http://www.analog. com/Analog_Root/static/techSupport/designTools/interactiveTools/dbconvert/dbconvert. html Using the link brings up up an error page from Analogue Devices (so it's found the right site, just the page no longer exists) saying Error We are sorry! The page you are looking for could not be found. Is there an alternative URL for the calculator please? Thanks - Dave (G0DJA) ___ Tiscali Broadband only £9.99 a month for your first 3 months! http://www.tiscali.co.uk/products/broadband/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Dave, The link works for me, but you may try this: http://www.analog.com/en/DCDesignToolsDisplay/0,3091,,00.html ;ten go to Audio/Video Products and select dBm/dBu/dBv Calculator. Good luck, Ahti OH2RZ On 15/04/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Original Message Cecil, A convenient on-line calculator for signal level conversions is this: http://www.analog. com/Analog_Root/static/techSupport/designTools/interactiveTools/dbconvert/dbconvert. html Using the link brings up up an error page from Analogue Devices (so it's found the right site, just the page no longer exists) saying Error We are sorry! The page you are looking for could not be found. Is there an alternative URL for the calculator please? Thanks - Dave (G0DJA) ___ Tiscali Broadband only £9.99 a month for your first 3 months! http://www.tiscali.co.uk/products/broadband/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Dave, Try this one: http://tinyurl.com/2qfpg 73, Dale WA8SRA [EMAIL PROTECTED] wrote: Original Message Cecil, A convenient on-line calculator for signal level conversions is this: http://www.analog. com/Analog_Root/static/techSupport/designTools/interactiveTools/dbconvert/dbconvert. html Using the link brings up up an error page from Analogue Devices (so it's found the right site, just the page no longer exists) saying Error We are sorry! The page you are looking for could not be found. Is there an alternative URL for the calculator please? Thanks - Dave (G0DJA) ___ Tiscali Broadband only £9.99 a month for your first 3 months! http://www.tiscali.co.uk/products/broadband/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Thanks for that, I realised, after sending the message, that the URL in the original message had some extra characters after the 'HTML' tag. Removing these allowed the link to work properly. Cheers - Dave (G0DJA) Original Message Dave, The link works for me, but you may try this: http://www.analog.com/en/DCDesignToolsDisplay/0,3091,,00.html ;ten go to Audio/Video Products and select dBm/dBu/dBv Calculator. Good luck, Ahti OH2RZ ___ Tiscali Broadband only £9.99 a month for your first 3 months! http://www.tiscali.co.uk/products/broadband/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
At 01:40 AM 4/15/2007, Sami Aintila wrote: Usually for audio applications dBm should be referenced to one milliwatt into a 600-ohm load. (Your dBm figure is using 50 ohms). In order to avoid confusion when we're measuring voltages, it's better to not use dBm at all. For voltages, it's probably easiest to use dBV referenced to one volt RMS. (There's also dBu which is equivalent to dBm @ 600 ohms.) To answer your original question, while the Delta 44 may not be a typical sound card, its input range (peak-to-peak) seems to be 11 Vpp. That's about 5.5 Vpeak, 3.9 Vrms, +12 dBV (+14 dBu). The maximum input level is 6 dB lower when using the consumer setting in D44's control panel. And using the lowest setting means another -6 dB. That would be 0 dBV == 1 Vrms. Maybe that's pretty close to a typical (cheap) sound card. Consumer vs Pro has to do with the different standard interface.. In the consumer world, the input is typically a RCA Phono jack with 47k nominal load impedance, and the sensitivity was set to match the output of a crystal pickup on a phongraph, where the big signal is tenths of volts. In the telephone world, it's 600 ohms balanced, as Sami indicates, and works in actual milliwatts, and tends to work with big signals being volts The Pro Audio world has pretty much adopted the MaBell phone conventions 73, Sami OH2BFO ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Thanks everyone for the answers, I suspected I had it wrong and I did. I have an output in dBm at 50 Ohms, using a transformer to convert the impedance from 50 ohms to 600 Ohms then output in DBU would be the voltage at 50 Ohms times the square root of the impedance ratio or 3.46 times higher than the 50 Ohm ? +14 dBm = 1.1V at 50 Ohms convert to 600 ohms with a transformer and you have 3.8V at 600 Ohms or 10.7V PP +26dBm gain prior to that and I end up with -12 dBm input or higher will start getting you in trouble. Anybody know where I can find a sound card with 180 dB dynamic range for less than $200? At 03:40 AM 4/15/2007, Sami Aintila wrote: Usually for audio applications dBm should be referenced to one milliwatt into a 600-ohm load. (Your dBm figure is using 50 ohms). In order to avoid confusion when we're measuring voltages, it's better to not use dBm at all. For voltages, it's probably easiest to use dBV referenced to one volt RMS. (There's also dBu which is equivalent to dBm @ 600 ohms.) To answer your original question, while the Delta 44 may not be a typical sound card, its input range (peak-to-peak) seems to be 11 Vpp. That's about 5.5 Vpeak, 3.9 Vrms, +12 dBV (+14 dBu). The maximum input level is 6 dB lower when using the consumer setting in D44's control panel. And using the lowest setting means another -6 dB. That would be 0 dBV == 1 Vrms. Maybe that's pretty close to a typical (cheap) sound card. 73, Sami OH2BFO On 4/15/07, k5nwa [EMAIL PROTECTED] wrote: What is the full scale input to a typical sound card? I'm thinking it's +10dBm or .7V, am I off my rocker? Cecil K5NWA www.qrpradio.com www.hpsdr.com Blessed are the cracked, for they shall let in the light. Cecil K5NWA www.qrpradio.com www.hpsdr.com Cum catapultae proscriptae erunt tum soli proscripti catapultas habebunt. (When catapults are outlawed, only outlaws will have catapults!) ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
Re: [Flexradio] Sound card input Voltage
Anybody know where I can find a sound card with 180 dB dynamic range for less than $200? If there was one, we would all have one. :-) -Tim, W4TME -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of k5nwa Sent: Sunday, April 15, 2007 1:56 PM To: Sami Aintila Cc: [EMAIL PROTECTED] Subject: Re: [Flexradio] Sound card input Voltage Thanks everyone for the answers, I suspected I had it wrong and I did. I have an output in dBm at 50 Ohms, using a transformer to convert the impedance from 50 ohms to 600 Ohms then output in DBU would be the voltage at 50 Ohms times the square root of the impedance ratio or 3.46 times higher than the 50 Ohm ? +14 dBm = 1.1V at 50 Ohms convert to 600 ohms with a transformer and you have 3.8V at 600 Ohms or 10.7V PP +26dBm gain prior to that and I end up with -12 dBm input or higher will start getting you in trouble. Anybody know where I can find a sound card with 180 dB dynamic range for less than $200? At 03:40 AM 4/15/2007, Sami Aintila wrote: Usually for audio applications dBm should be referenced to one milliwatt into a 600-ohm load. (Your dBm figure is using 50 ohms). In order to avoid confusion when we're measuring voltages, it's better to not use dBm at all. For voltages, it's probably easiest to use dBV referenced to one volt RMS. (There's also dBu which is equivalent to dBm @ 600 ohms.) To answer your original question, while the Delta 44 may not be a typical sound card, its input range (peak-to-peak) seems to be 11 Vpp. That's about 5.5 Vpeak, 3.9 Vrms, +12 dBV (+14 dBu). The maximum input level is 6 dB lower when using the consumer setting in D44's control panel. And using the lowest setting means another -6 dB. That would be 0 dBV == 1 Vrms. Maybe that's pretty close to a typical (cheap) sound card. 73, Sami OH2BFO On 4/15/07, k5nwa [EMAIL PROTECTED] wrote: What is the full scale input to a typical sound card? I'm thinking it's +10dBm or .7V, am I off my rocker? Cecil K5NWA www.qrpradio.com www.hpsdr.com Blessed are the cracked, for they shall let in the light. Cecil K5NWA www.qrpradio.com www.hpsdr.com Cum catapultae proscriptae erunt tum soli proscripti catapultas habebunt. (When catapults are outlawed, only outlaws will have catapults!) ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/ ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
[Flexradio] Sound card input Voltage
What is the full scale input to a typical sound card? I'm thinking it's +10dBm or .7V, am I off my rocker? Cecil K5NWA www.qrpradio.com www.hpsdr.com Blessed are the cracked, for they shall let in the light. ___ FlexRadio mailing list [EMAIL PROTECTED] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
